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Post by LuK on Jun 14, 2012 14:49:47 GMT
Ah, OK. Now all is clear! ReThanks, bye.
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Post by LuK on Jun 26, 2012 22:35:11 GMT
When a loudness version (like Indeed G3) of the Sunrise II?
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Post by Deleted on Jun 27, 2012 5:08:05 GMT
never.... It's a DIY project so if an owner wants one they can simply make it. All that's needed is a volpot with a centretap and a few extra components. AFAIK the G3 is the only headphone amp with 'loudness'. Loudness only works correctly (as intended) when the sound pressulre levels match the Fletcher Munsun curves which is impossible in practice for lots of reasons. Also it should also boost treble a bit, but the G3 one doesn't. Otherwise it will just be a bass boost that is somehwat volpot dependent. That's what it does on the G3... it's not loudness but a bass boost. Some headphones will benefit though, not a very hifi thought though with people falling over 'bitperfect' reproduction e.t.c. For the same reason there won't be a version with tone control either. There will be a fully 'auto bias/auto heater voltage' version of the Horizon but it won't be class-A but won't get hot as well. I expect this to be available around fall of 2012.
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Post by Deleted on Jul 2, 2012 19:12:47 GMT
I don't know if Ian recognises this amp anymore as it has undergone some (radical) changes. It has an extra PCB below the original one. On that PCB is autobias and autoheater select (pop in a dual triode 6V or 12V tube and it completely sets itself) Also a high-low output resistance switch is below the output socket (so no need to take the top off anymore to set jumpers) Also I moved the power switch to the front and installed a green 'on' LED and red 'stand-by' LED. Technically it has also been upgraded to Sunrise-II (cathode and relay circuit) and a 5 Ohm minimal output resistance and has an RCA line out. This line out only has 4x gain where as the Sunrise-II / Horizon has 20x gain as a pre-amp.
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Post by Deleted on Jul 2, 2012 19:37:43 GMT
It's my baby ........ It's developed an extra knob. It's turned into a 2 up 2 down. You've been busy, Frans. I'm absolutely stuck on the Horizon. It is absolutely superb. The funny thing is that I haven't heard one single noise or buzz or phone ever on it. Considering the problems I had with the Bravo, it's amazingly quiet too. You should auction that Frans.......
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Post by misterrogers on Jul 3, 2012 4:32:33 GMT
Fran - is that by chance going to be offered as a sunrise II upgrade? I'm the proud owner of 00000001.
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Post by Deleted on Jul 3, 2012 6:44:55 GMT
The autobias circuit is something that could be retro-fitted but requires desoldering of parts. For the Horizon this will be more difficult.
I had thought about that for about a year now and maybe I will make a small SMD PCB that can be retrofitted (in Bravo thingies as well) but the mechanical fixing of it is another matter. Auto heater select will be very difficult to implement as a retrofit and would require better than average soldering and desoldering skills, disconnecting of pads to ground e.t.c.
For now there are no plans..
The only difference with Sunrise-II is the auto bias/tube detect and lowered output voltage for RCA. This last bit can be easily done for Sunrise-II/Horizon if needed (in case the gain as a pre-amp is too high) by changing a resistor value and adding one (per channel) below the output RCA (from pin to ground)
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Post by loevhagen on Jul 8, 2012 12:51:11 GMT
: P.S. I just removed the original Russian 6N23P, and plugged in one of my highly prized Telefunken tubes (an ECC88) and lo and behold! The skies opened up, and the clarity and definition became amazing! Did the Telefunken keep the good bass response the 6n23p has?
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Post by Deleted on Jul 8, 2012 20:49:40 GMT
Hi loevhagen and welcome to the forum
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Post by loevhagen on Jul 8, 2012 20:56:58 GMT
Thanks. I got one of these babies (Sunrise V2) and I must admit I didn't expect the sound quality it delivers. Absolutely lovely with the 6n23p tube.
I just had to order some other tubes to make my own mind up on tube rolling this little amp.
The only downside, is that that the amp's gain is a bit over the top. I partly solved that by adjusting the internal gain via dip-switches in my DAC (Violectric V800) from +15dBU and down to +6dBU.
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Post by Deleted on Jul 8, 2012 21:44:18 GMT
: P.S. I just removed the original Russian 6N23P, and plugged in one of my highly prized Telefunken tubes (an ECC88) and lo and behold! The skies opened up, and the clarity and definition became amazing! Did the Telefunken keep the good bass response the 6n23p has? Hello loevhagen, The Telefunken ECC88 tube actually improved the bass response of the Horizon by tightening it. It rendered a certain clarity, transparency, and openness to the SQ, bordering on being almost clinical (though still very musical!). By revealing the inner voices, IMHO, and to MY ears, this is a big advantage in heavily textured orchestral passages. This may not appeal to people who prefer a "warm" (slightly muddy?) bass response for "easy listening". It is all a matter of taste. Being a professional, classically trained musician, I listen to music actively (rarely as background "easy listening"); in other words, I want to hear every note of the music performance as realistically as the equipment allows. Cheers!
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Post by loevhagen on Jul 10, 2012 20:55:10 GMT
Sounds comforting. Thanks. I really enjoy this amplifier.
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Post by loevhagen on Jul 15, 2012 19:54:18 GMT
Question: I tried a 5751-EH in the Project Sunrise II today. Set the voltage jumper to 12V, disconnected the headphones and DAC and switched the amp on. The bias LEDs indicated to high bias, so I started to turn the adjustment counterclockwise. I got to the mechanical lowpoint ( small clicks from the bias pot), but the Bias To High LED still glowing. Hm. What I am doing wrong?
Tried 3 other tubes (6922 / E88CC) and no problem to adjust bias - using the voltage jumper in the 6V position for these tubes, of course.
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Post by Deleted on Jul 15, 2012 21:35:11 GMT
The 5751 can be viewed as an ECC83 (which already runs at a rediculously low current in low voltage amps) with even lesser gain (in return it's lower in noise and microphonics) so you probably reached the lowest possible anode current. If you are really set to using this tube (might be noisy on this low voltage) you could replace the 20k bias pots for 50k ones. This will lower the voltage.
Try to short the cathode resistor, see if it helps a bit. Also try to use it with or without the input coupling caps (jumper setting)
When using a voltmeter what is the lowest possible voltage you get ?
It probably is near the border of what's possible with this tube.
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Post by loevhagen on Jul 18, 2012 23:37:10 GMT
Ah. Thanks. I forgot about the higher bias that the input caps add when bypassed.
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Post by loevhagen on Jul 18, 2012 23:42:30 GMT
The PSii have regained my love in the Audeze LCD-3: I must admit, that the Siemens tube surpass the stock 6n23p from the 80s. The TFK plays even more "neutral" than the Siemens tube from 1974. Like both, but love the Siemens in the PSii for both the HE-500 and the LCD-3. Next - and even better amp in the pipeline? I'll buy it.
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Post by morpheus on Sept 12, 2012 22:26:25 GMT
Greetings from Norway here I have now own my Project Sunrise for about 5 month. I must say I am very very happy with this amp!! However I do have some questions: I have ordered: www.cryoset.com/catalog/product_info.php?products_id=243&osCsid=e4m0cjj2bnkg77k74htqu0s6g7 But I have some problems to get the bias right. The LED's indicate that the bias is to high. I have turned the screw's as far up as I deer... If I turn them more I got a "click" sound from them. When I meassure at Vdc20 I get the value of 15.30 and 16.00. The sound from my amp is still very good, but will this harm my amp and the tube? I also wounder if there would be any point in switching the potmeter due to some inbalance at low volume. If I do, can I expect better soundquality if I buy a good one? I have puchased the DC2 and look forward to see if that can further improve this brilliant amp. I ordered this amp pre-build from Jeremy. I'm not a skilled DIY'er myself... yet but I'm quite keen on trying some more mods on it if there is any .
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Post by Deleted on Sept 13, 2012 5:01:48 GMT
Greetings from Norway here I have now own my Project Sunrise for about 5 month. I must say I am very very happy with this amp!! However I do have some questions: I have ordered: www.cryoset.com/catalog/product_info.php?products_id=243&osCsid=e4m0cjj2bnkg77k74htqu0s6g7 But I have some problems to get the bias right. The LED's indicate that the bias is to high. I have turned the screw's as far up as I deer... If I turn them more I got a "click" sound from them. When I meassure at Vdc20 I get the value of 15.30 and 16.00. The sound from my amp is still very good, but will this harm my amp and the tube? I also wounder if there would be any point in switching the potmeter due to some inbalance at low volume. If I do, can I expect better soundquality if I buy a good one? I have puchased the DC2 and look forward to see if that can further improve this brilliant amp. I ordered this amp pre-build from Jeremy. I'm not a skilled DIY'er myself... yet but I'm quite keen on trying some more mods on it if there is any . Welcome to the forum. It appears as though the tube has very low emission (possibly because of the cryo). Changing the bias pot for higher value will cure this. The amp nor any parts will be harmed because of this higher bias. the clicking sound of the adjustment pots indicates the end, They can not be damaged, the clicking sound is the end of the worm gear thread inside the pot. I suggest you try to contact Jeremy and ask for trimpots of a higher value and mention the volpot issue. He is a hard man to reach and even I haven't had contact with him for weeks myself. If you cannot reach him though his website or e-mail let me know.
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Post by Deleted on Sept 13, 2012 6:01:08 GMT
Frans Have you had previous experience with Cryo treated tubes ? I can't help but feel that exposing a filament in a light globe, let alone a fragile filament in a vacuum tube to Cryogenic treatment would be a risky procedure,even if it did have some magic side effect. Alex
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Post by Deleted on Sept 13, 2012 6:46:58 GMT
Cryo is normally used for hardening steel (tools) so the wear is less. Tubes do not have steel and the cathodes usually are made of Nickel with an oxide on it that emits the electrons when heated.
Little is known about the effects of cryo on nickel and oxides. Beautifull theories and testimonials are a plenty though.
The biggest problem with cathodes is impurities of the Nickel and these will not be 'cured' by cryo treatment. Perhaps Nickel get's slightly harder but there is no wear and tear of the metal...
Personally I seriously question if some tubes that are sold as being cryo treated may not have undergone the actual treatment at all... you cannot check it and have to believe the seller.
a normal 6N23 shouldn't have any problems being adjusted properly. In high voltage tube amp design (most out there) it wouldn't even be noticed if emission is lower. IF the lower emission is indeed caused by (wrongly or correctly done) cryo treatment is merely a 'hunch' and not based on experience.
The magic effect it would have is far from my area of expertise and have NO experience with it.
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Post by morpheus on Sept 14, 2012 8:33:36 GMT
Thanks for the reply and the welcome Frans . It is interesting that it is the cryo-treatment that may caused the problem with adjusting the bias. I thought it would be safe to buy that tube since it is quite similar to the stock tube in my amp. Jeremy had some delaying answering my email, but he has been away due to business and he have now replied. He is very helpful and offer me to send the amp back to him for an upgrade. However I think I will use this opportunity to practice my soldering skills and do the modding myself. I have some more questions thou. In the manual from 2011 the Vdc 20 measuring should be at 13.5 volt, but in the 2012 manual it is 12.0 volt. Is it the latter that is right? If the bias is to high, can I expect the tube to oscillate more even thou it's not hear able ? When I look in the 2012 manual the value of the volume pot should be 20k, back on mine volume pot it stands 10k. I use a Hegel HD 11 DAC, and the sound is already very high at 9'o'clock. Would it be wise to switch the volume pot to a value of 100k?. I got this standard 100k potentiometer from Audio Note in mind: www.audionote.co.uk/comp/atten.shtml or do you have other recommendations? We have a quite nice thread about PSii on the biggest Norwegian hi-fi forum www.hifisentralen.no/forumet/hodetelefoner/63940-project-sunrise-horizon-og-ember.htmlWill the new Ember-amp be a sonically upgrade from PSii when using headphones up to 120ohm? Regards. Carl.
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Post by Deleted on Sept 14, 2012 9:18:09 GMT
It is interesting that it is the cryo-treatment that may caused the problem with adjusting the bias. I thought it would be safe to buy that tube since it is quite similar to the stock tube in my amp. It's just my (uneducated in this area) guess, could be wrong about it might be due to other reasons as well. In the manual from 2011 the Vdc 20 measuring should be at 13.5 volt, but in the 2012 manual it is 12.0 volt. Is it the latter that is right? Yes in the Sunrise it was 13.5V in the SR-II it is 12V due to different cathode configuration. In the first manual(s) Jeremy had not altered this. The bias LED's are set to '12V adjustment' or at least should be. If the bias is to high, can I expect the tube to oscillate more even though it's not hearable ? There is never an oscilation in any of the bias settings. The bias setting has to be set so maximum output power is available with symmetrical clipping (should the clipping level be reached). When I look in the 2012 manual the value of the volume pot should be 20k, back on mine volume pot it states 10k. I use a Hegel HD 11 DAC, and the sound is already very high at 9'o'clock. Would it be wise to switch the volume pot to a value of 100k?. I got this standard 100k potentiometer from Audio Note in mind: www.audionote.co.uk/comp/atten.shtml or do you have other recommendations? Volpot issue: Originally we went for 20k log type volpot BUT at a certain point in time they were not obtainable and 10k is a good enough load for 99% of all the sources out there so changed it to 10k after a while. Imbalance issues: (L/R difference) is simply caused by the construction (size) of the volpot and it having log-type characteristics. Jeremy buys loads of them and selects them by hand for optimal balance. Gain issues: Gain will not alter nor will the travel (position and how loud it plays) by changing the value of the volpot. The gain of these amps is determined by the tube itself. In case you want a more use-able volpot range the overall gain can be lowered by changing 2 resistors and because of that 2 capacitor values as well. R7 needs to be increased. For a 6dB reduction R7 -> 10k , C3 must be lowered to 22pF for a 10dB reduction R7 -> 27k , C3 must be lowered to 10pF Perhaps needless to say the imput resistance of the amp will also increase. with R7 - 10k R in becomes 20k with R7 - 27k R in becomes 47k Will the new Ember-amp be a sonically upgrade from PSii when using headphones up to 120ohm? The Sunrise-II can drive HP's ranging from 16 to 300 Ohm but drives the 16 to 120 Ohm impedance to high levels. The Horizon can drive 32 to 2kOhm HP's but drives the 120 to 600 Ohm impedance HP's to high levels. The upcoming Ember, which is still in developping phase as I now also want to jumper set maximum output power levels so you can 'protect' low power headphones from being accidentally destroyed by high output powers the Ember can reach in low impedance headphones. It will have 3 different OUTPUT resistances as well to 'tune' the HP to the amp (and your ears). If it will be sonically better I will let others decide and am not going to promote my designs with superlatives on SQ...
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Post by morpheus on Sept 14, 2012 10:56:50 GMT
thanks a lot for your thoroughly replay!
So if I go for the 100k potentiometer that i linked to, it should be working fine?
Carl
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Post by PinkFloyd on Sept 14, 2012 11:16:16 GMT
"cryo" is a word that is used to treble the price... Absolute bunkum IMO and I totally agree with you Frans, how do you KNOW your valve has been deep frozen?
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Post by Deleted on Sept 14, 2012 11:25:29 GMT
thanks a lot for your thoroughly replay! So if I go for the 100k potentiometer that i linked to, it should be working fine? Carl as long as it is a LOG type it'll work O.K.
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